A technique known as electron beam activated chemical etch (EBACE) has been developed as an analytical tool in semiconductor fabrication. In this technique an etchant, typically in the form of a gas or vapor, is introduced into the field of view of a scanning electron microscope proximate the surface of a target, such as an integrated circuit device. The etchant is usually one that is known to etch the target material upon electron-beam induced activation. The electron beam from the electron microscope activates the etchant resulting in etching of the target surface in locations exposed to both the etchant and the electron beam. The target surface can be etched layer by layer with real time imaging of each layer.
It is within this context that embodiments of the present invention arise.